(a) Field of the Invention
The present invention relates to a radio frequency identification (RFID) reader, a method thereof, and an RFID data processing method. More particularly, the present invention relates to a radio frequency identification (RFID) reader for reading a plurality of RFIDs at a high speed, a method thereof, and an RFID data processing method.
(b) Description of the Related Art
An RFID system using the RFID includes a reader and a tag, in which the reader queries the tag of an ID and detailed information of the tag through a radio communication link, and the tag receives power needed for processing by the tag from the reader through the radio communication link and applies energy caused by the power to calculation on the tag or communication with the reader. In this instance, the conventional RFID system uses a round having a predetermined number of slots so as to quickly identify a plurality of tags. A slot is a time for the tag to transmit a tag ID as a response, and one slot represents a time for the reader to transmit a specific message and receive a corresponding response.
Goods identification using the RFID system is very useful in the delivery and distribution fields, such as for tracking assets and automatically checking stocks. Particularly, the RFID usage in the delivery and distribution fields attaches an RFID to each product before the product is delivered, and builds product information corresponding to a tag ID of the attached RFID in a database, thereby efficiently managing the products.
Published Korean Application No. 2005-0047670 that uses an RFID discloses “Method and apparatus for reading RFID attached product.”
The prior art installs an RFID reader that is movable among products and checks the stock of products in order for a vending machine to read the RFID having various frequencies, and uses a reader at a product outlet to collect sales information, efficiently check stock, and acquire sale volumes.
The conventional RFID system uses a plurality of rounds having a predetermined number of slots so as to identify the RFID attached to the product, and the RFID generates a response depending on the round size of the reader to manage the product.
The conventional RFID system fails to identify a tag ID in the corresponding round and goes to the next round to identify the tag ID when at least two tags having the same slot number in one slot are generated to generate a collision in the radio communication link. That is, when a collision is generated in the corresponding round, the entire tag identifying time for the reader to identify the tag is increased irrespective of the number of tags to be identified.